Rotary kiln chain arrangement



Oct. 26, 1943. w. c. JoHNsoN I ROTARY KILN CHAIN ARRANGEMENT Filed om.y 5; `1942 Patented Qct. 26, 1943 y Williamfohnson, Wauwatosm'Wis., assigne-r to4 Allis-ChalmersManufacturing Company, Milv waukee, Wis.,`a corporation of Delaware V 1942, Serial No. '160,919v l 211 claims. (cl. 2613-32) Application october This invention pertains to chain arrangements Y for rotary drums, and mores'p'ecically for rotary kilns.

'While various chain'arrangements for rotary kilns are known, most of such `known arrangements utilize a plurality of chains which are fastened at their ends to the interior of thekiln, so that the intermediateportions onlyof the chains are effective in wiping the inner surface `of the kiln to prevent buildingvup mud rings therein.- Such mudrings are objectionable in' that' they interfere with the flow lof materialand l`gases through the kiln, and seriouslyre'duce 'thetapacity ofthe kiln. l l It is an object of this invention to provide a chain arrangement in which the chains are "Inovable circumferentially orcircurnferentially and axially in theirlentirety, so that the complte length of each chain is useful in wiping the innerl surface of the kiln, 1 l

It is a further object of this invention to provide a chain system in which each chain is loosely attached at its ends to a circumferential or helical bar adjacent the inner surface of the kiln and spaced therefrom, in such manner that the chain ends are free to slide along the lengths of such bars during rotation of the kiln.

In the drawing attached hereto:

Fig. 1 is a vertical sectional view of a kiln illustrating one embodiment of this invention, taken along the line I-I of Fig. 2;

Fig. 2 is a longitudinal section of the kiln taken along the line II--II of Fig. 1;

Fig. 3 is a longitudinal sectional view similar to Fig. 2, but illustrating a modification in which the chain supporting bars extend helically within the kiln; and

Fig. 4 is a fragmentary longitudinal sectional view similar to Fig. 2, but illustrating a modification in which the chains are arranged to overlap.

The drawing illustrates a standard kiln having a shell I0 provided with an inner lining Il, the feed end of the kiln being flanged at I2. In the modification shown in Figs. 1 and 2, a plurality of segmental circumferential bars I3 are arranged adjacent to the kiln lining, but spaced therefrom, the rods being supported in any suitable manner by means of radial supporting members It, leaving each rod substantially unobstructed throughout its length. A plurality of slack chains Il are mounted to extend between spaced bars I3, the chains being attached to the bars by means of rings I6 which are free to slide along the arcuate length of the bars. Material may be fed to the kiln by means of feed chute I8.

Seriousiproblems have arisenxinfeedingnmatel rial through-a rotary kiln, particularly such wet materials as cement slurry. There is a tendency for the material to-build up a ffmud ring in the kiln, thereby restricting the npassage of material through the kiln. Theresultant decrease'in capacity has been only partially avoided by existing chain systems.. Chain systems ofthe prior art have usuallyibeen'fastened at one or both ends, so that While the intermediate portion of the -Y chain may be useful in wiping along the surface ofthe kiln,` the section of the kiln adjacent to V:the points of` attachment ofeach chain' has been substantially unaffected by the wiping action` of `the chains, so thatmud rings were free tocollect 1 at those; points.

In 'the ch'ain. system of this invention, however, as the kiln rotates the chains and their attaching rings tend tomove to the lowermost part ofthe bars to whichy they are'.r connected, as shown in Fig. 1. For example, at ,theV left of Fig. 1 it will be noted that the` chains are located at the trailing end of supporting bars I3, assuming the kiln is rotating in a clockwise direction. After the kiln has rotated through an angle such that the supporting bar has passed beyond its highest elevation it will be seen that, with the aid of gravity, the chain ends move along their supporting bars until they are located at the leading ends of the bars, so as to locate them in position to sweep the inner surface of the kiln after they pass the lowermost position. The chains, being heavier than the material handled, tend to break through the banked material, keeping it loose, and preventing objectionable adherence to the lining, Therefore a much more efficient action in keeping the inner kiln surface clean is brought about by this manner of attaching the chains. As the chains slide forward after passing the highest point, the rings, bars and chain ends also are cleared of any adhering material.

Fig. 3 illustrates a modification in which the chain supporting bars I3' extend helically within the kiln, rather than in a plane normal to the kiln axis. The result of this helical arrangement of the chain supporting bars is that as the chains slide from one end of their supporting bars to the other the chains move axially as well as circumferentially, thereby promoting a freer movement of the material Within the kiln.

Fig. 4 illustrates a further modification, similar in some respects to that of Figs. 1 and 2, but in which the chains Il' are longer and attached to alternate bars, their middle portions passing between the intermediate bar and the lining of the shell. Two chains l1 thus partially overlap,

increasing the scraping action.

It is obvious that other iexible bands may be substituted for the chains referred to in the specication and claims, and are deemed to be included Within the term chains The term freely attached as used in the claims isintended to define an attachment in which the chains are free to move-- alongithe lengths of'their `'supporting bars.

The chain system described herein is illustrative only, the scope of the invention being limited only by the scope of the ichairrs herein.

It is claimed and desired to secure byLetters Patent:

1. In a rotary cylindricalIdrurnfaLplurlityo `chains adjacent the interior surfaceofsa'iddrum,

and means for attaching chains to .sai'didrutnor free movement in their entirety alonga substantial surface of the interior of said drum.

'f-chains 'adjacent the interiorfsurface of vsaidl drum -"andarranged approximately longitudinally'the'reof, *and 'means' for attachingy sai-d chains to ysaid fdrum'vvith considerable'freed'omof kmovementof I thefpointsfof'attachment'of said chains circum- Aferentially of said -drumywhereby said chains are f1-'ee to move in their `entirety circumferentially "Within said drum during `rotation thereof.

*3. Ina` rotary kiln; bars fof limited length sup-4 v. l'po'rted Within sai'dkiln and spaced from thein- "'fterior jsurface thereof, and .1a plurality of-chains Vfastened to said barsfor free-movementfalon the lengths-of said bars.

f4. --I-n a rotarykiln,':bars1of'limited.length supported Within said kiln and spacedfrom the inner fs'urfa'ce thereof,fand a plurality of'cliainsha'ving their 7ends freelyattach'ed to'sai'd 'barsf forv free rnovement along the lengths` of-said bar.

5; Ina rotary kiln,1` circumferential; barssupported within said kiln andspaced yfrom the inner Vsurface thereof, yanda plurality of lSchains'aeach -vx-:lia'in's' having each endifree'ly attachedV to one of said barsrfor l-free movement `rvalong; said bar,

whereby said chains are free to move circumf 'iferentially in their entirely'along the inner surf face of the r'ki-ln during rotation thereof.

'7.` In a rotarykiln, a. plurality of bars adjacent *j-toithe linnersurface of said kiln and spaced therefrcmuadialrmernbers' supporting said bars with- `vin"saidikiln,"arlurality of chains extending beftweenicertain '.ofsaid bars, and rings slldable along the length of said bars connecting said 4dchains `to said bars, whereby said chains are free tol-fmcveli-n their. entreiyfcirumferemieliy 0f Y -saidkiln ,during-frotatienfthereof 4 y 8. A structure as defined in claim 7, saidrhars `lbeing arranged rin, -planes I.perpendicular the axisofsaidakilnu Y 1 9.. fA structurel as deiined in` c lairn '3, .certain {if-saidk bar-s, being: arranged helically iwi'thins'ald akiln, iis/herebyl said chains :arelfee gto l'xnoxzein ,.--their entirety in-circumferential -and axialdirec- .tionsyvithin said-,kiln duringrotation thereof.

:said chrainsbeing-attachedV to .alternateba-rg por- Qverlapnns betr/##211 `tions of, said .chainspartially certain adjacent bars. 4;. fl-1. A structure .asde iineddn .claim-7, said bars @being f (arranged in :planes perpendicular lto l the l:axis-fufsaidkilnweach`- offsaidchains beinagat- `-taclled` to {altem-rate bars.; the middle '..portion Vof f `each chai-n `lpassi-ng freely rbetvveenl.an l.intermediate bar and said inner surface of.sai'c'i'lfiln,`

UonNsoN.

'CERTIFICATE OF CORRECTION.

Patent No. 2,552,721 October 26, 1911.5

WILLIAM C. JOHNSON.

It is hereb;r certified that error appears in the printed specification ofthe above numbered patentrequiring correction-as follows: Pagek 2, 'second column, line l2, claim 6, for "entirely" read --entirety--g and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

sign'ea'and sealed this 7th dey of Deeenoer,l A. D. 1915.

. AHenry Van Arsdale, (Seal) Acting Commissioner` of Patents. 

